Headers.add(_key, _value, **kw)[source]

Add a new header tuple to the list.

Keyword arguments can specify additional parameters for the header value, with underscores converted to dashes:

>>> d = Headers()
>>> d.add('Content-Type', 'text/plain')
>>> d.add('Content-Disposition', 'attachment', filename='foo.png')

The keyword argument dumping uses dump_options_header() behind the scenes.

New in version 0.4.1: keyword arguments were added for wsgiref compatibility.